The biggest issue I have with BBQ flavored anything is the caramel coloring added to the bbq sauce. Caramel coloring is considered "safe" but since I am highly sensitive, it gives me issues every time.
I use the natural ones because I don't like any more preservatives than necessary. I haven't had any issues with the Skippy natural or the Peter Pan natural. It is peanuts, sugar, palm oil, and salt so no gluten containing items.